This soup made me happy because it was warm and comforting on a cold day, used squash and herbs from the garden, and turned out super smooth. I left the herbs whole and removed them after simmering to make a silkier texture. Also, I roasted the squash unpeeled and then removed the peel because my hands get itchy / flaky if I handle raw butternut for too long. Plus, it's easier to peel after it's cooked. —pantryhero
Preheat the oven to 425º. Place the butternut chunks on a Silpat- or parchment-lined baking sheet, brush with the melted butter, and sprinkle with 1/2 tsp. of the kosher salt. Bake until tender, about 30 minutes. It’s ok if the squash is not not 100% cooked because it’s going to simmer in the soup for a while. When the squash is cool enough to handle, use a paring knife to remove the peel from the chunks.
Heat the oil in a soup pot over medium to medium-low heat. When the oil is warm, add the shallot and the remaining 1/4 tsp. kosher salt, and sauté until golden brown, about 4 minutes.
Add the garlic. Stir constantly until fragrant, about 1 minute.
Add the beans (with the bean water—no need to rinse and drain), the chicken stock, the peeled butternut chunks, the parsley, and the sage. Turn the heat up and bring to a boil, then reduce heat and simmer for 20 minutes.
Take the pot off the heat. Remove the sage and parsley sprigs. Add the nutmeg and brown sugar, and let cool for a little while.
Puree with an immersion blender until completely smooth. (If you don’t have an immersion blender, use a food processor or regular blender, puree the soup in batches, and return to the pot; just make sure that the soup is plenty cool before you do this because the steam released when you blend hot liquids can blow the top off your blender and make scalding soup splatter all over you (I say from prior experience…).)
Taste the soup. Season with white pepper and add more salt to taste.
Just before serving, top each bowl of soup with about 2 Tbsp. of the Parmesan and a small handful of the toasted pine nuts.